具体实现方法如下：
<?php function getipaddress() { // 取得当前用户的ip地址 if (getenv('http_client_ip')) { $ip = getenv('http_client_ip'); } elseif (getenv('http_x_forwarded_for')) { $ip = getenv('http_x_forwarded_for'); } elseif (getenv('remote_addr')) { $ip = getenv('remote_addr'); } else { $ip = $_server['remoe_addr']; } return $ip; } function writeover($filename,$data,$method = 'w',$chmod = 0){ $handle = fopen($filename, $method); !handle && die("文件打开失败"); flock($handle, lock_ex); fwrite($handle, $data); flock($handle, lock_un); fclose($handle); $chmod && @chmod($filename, 0777); } function count_online_num($time, $ip) { $filecount = './count.txt'; $count = 0; $gap = 900; //15分钟不刷新页面就 if (!file_exists($filecount)) { $str = $time . "\t" . $ip . "\r\n"; writeover($filecount, $str, 'w', 1); $count = 1; } else { $arr = file($filecount); $flag = 0; foreach($arr as $key => $val) { $val= trim($val); if ($val != "") { list($when, $seti) = explode("\t", $val); if ($seti ==$ip) { $arr[$key] = $time . "\t" . $seti; $flag = 1; } else { $currenttime = time(); if ($currenttime - $when > 900) { unset($arr[$key]); }else{ $arr[$key]=$val; } } } } if ($flag == 0) { array_push($arr, $time . "\t" . $ip); } $count = count($arr); $str = implode("\r\n", $arr); $str.="\r\n"; writeover($filecount, $str, 'w', 0); unset($arr); } return $count; } $time = time(); $ip = getipaddress(); $online_num = count_online_num($time,$ip); echo $online_num; ?>
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以上就是php统计网站在线人数的详细内容。